<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <style>
        div{
            width: 200px;
            height: 400px;
            /* 上边框写法 */
            border-top: 2px solid red;
            border-left: 1px solid green;
            border-right: 1px solid blue;
            border-bottom: 1px solid pink;
        }
        
        input{
            /* border-top: none;
            border-right: none;
            border-left: none;
            border-bottom: 1px dashed red; */
            /* 四个边框都去掉 先写大的，后写小的 */
            border: none;
            border-bottom: 1px dashed red;
        }
    </style>
</head>
<body>
    <div></div>
    用户名: <input type="text"><br>
    密码: <input type="password">
</body>
</html>